The reputation of the Tesco management for sure-footedness has taken another knock, with Britain's biggest retailer scrapping the online used car site it set up a year ago.Tesco Cars was set up in April 2011 with lofty ambitions to offer up to 3,000 cars for sale each month, but came nowhere near the upper level of its target range. According to the Guardian newspaper, the online joint venture with Carsite was selling around 150 cars a month at the end end of last year, as it struggled to get a decent supply of cars.Tesco had a 25% stake in the Tesco Cars joint venture. "The customer response has been positive and shows the value of a trusted brand in this market, but securing a good supply of cars has been difficult and we would always want to deliver the best range for customers," a statement from Tesco on the Tesco Cars web site said."Given time we would have overcome the challenge but at the moment it's right to focus on our core business," the statement continued, in a reference to the group's struggle to maintain market share in its UK supermarket business.Tesco has also decided not to proceed with its household maintenance business, Tesco Home Services, after a lacklustre trial period. JH